28420634921 has 8 divisors (see below), whose sum is σ = 32481760320. Its totient is φ = 24359768208.

The previous prime is 28420634911. The next prime is 28420634933. The reversal of 28420634921 is 12943602482.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 28420634921 - 2¹⁰ = 28420633897 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28420634911) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 337550 + ... + 413256.

It is an arithmetic number, because the mean of its divisors is an integer number (4060220040).

Almost surely, 2^28420634921 is an apocalyptic number.

It is an amenable number.

28420634921 is a deficient number, since it is larger than the sum of its proper divisors (4061125399).

28420634921 is an equidigital number, since it uses as much as digits as its factorization.

28420634921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 129343.

The product of its (nonzero) digits is 165888, while the sum is 41.

The spelling of 28420634921 in words is "twenty-eight billion, four hundred twenty million, six hundred thirty-four thousand, nine hundred twenty-one".